Photo-Cross-Linked Laminarin-Based Hydrogels for Biomedical Applications

Laminarin is a low-molecular-weight (<10 kDa) glucan found in brown algae made up of β(1→3)-glucan with β(1→6)-branches. This is one of the most abundant carbon sources in the marine ecosystem. Laminarin has been found to possess various biological interesting properties, such as antioxidant and antimicrobial activities. An attractive feature of laminarin is its inherently low viscosity and high solubility in organic and aqueous solvents that facilitate processing. This makes laminarin an appealing material for the development of new hydrogels that can be easily injected through minimally invasive procedures or used for microfabrication of hydrogels. An approach for synthesizing photo-cross-linkable laminarin hydrogels is presented in this work for the first time. Photo-cross-linkable laminarin was prepared by chemical modification with acrylate groups. The synthesized photo-cross-linkable laminarin material provides the basis for the development of a new injectable system for biomedical purposes that could be used alone or with encapsulated cells or biological molecules. The cross-linking of the methacrylated laminarin is straightforward via photoinitiated polymerization. The possibility to control the methacrylation degree of laminarin and to prepare solutions up to at least 15% w/v permits us to obtain hydrogels with tuned and wide range of stiffness and swelling. Furthermore, the encapsulation of human-adipose-derived stem cells encapsulated in the photo-cross-linked hydrogels demonstrated in vitro biocompatibility.